Raspberry plant cv. `Wilhelm`

ABSTRACT

A new and distinct cultivar of red raspberry plant named `Wilhelm`, which is particularly characterized and distinguished by its very attractive fruit and its high yielding capacity on both primocane and floricane crops.

BACKGROUND AND SUMMARY OF THE NEW CULTIVAR

This invention relates to a new and distinct cultivar of raspberry plant that has been given the cultivar name or denomination `Wilhelm`. The new cultivar was developed from hybridization of the selection B175-3 (an unpatented proprietary cultivar) as the seed parent with the selection B8-4 (an unpatented proprietary cultivar) as the pollen parent. The parents were crossed by Stephen Wilhelm in 1986, whereafter fruit and seed were collected to produce seedlings for field planting in Watsonville, Calif. in 1988. The new cultivar was selected from these seedlings by Carlos Fear in 1989 for its ease of harvest and attractive, well-flavored fruit. Since its selection the `Wilhelm` plants have been evaluated in noncommercial experimental plantings in Oxnard and Watsonville, Calif. The cultivar has been asexually propagated by in vitro shoot tip culture, root sucker division and root cuttings, and has been shown to maintain the desired and distinguishing characteristics after propagation over several generations.

The `Wilhelm` raspberry plant produces a mid-season primocane crop which begins in mid August and continues until early-mid November. The floricane crop begins in mid-late May and continues until early July. Both the primocane and floricane yields (about 7.4 to 11.8 T/acre and about 4.7 to 8.8 T/acre, respectively) are high relative to other comparable cultivars. The fruit of the `Wilhelm` raspberry plant is very attractive, with small drupelets of a bright red color which darkens only slightly after harvest.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a photograph of a `Wilhelm` primocane mature leaf and fruiting shoot, showing various stages of fruit development.

FIG. 2 is a photograph of a `Wilhelm` primocane shoot.

FIG. 3 is an interpretative drawing showing the cultivar banding patterns for the enzymes, MDH (malate dehydrogenase), PGI (phosphoglucoisomerase) and PGM (phosphoglucomutase).

DETAILED DESCRIPTION OF THE NEW CULTIVAR

Throughout this specification, color names beginning with a small letter signify that the name of the color, as used in common speech, is aptly descriptive. Color names beginning with a capital letter designate color values based on the R.H.S. Colour Chart published by The Royal Horticultural Society of London, England.

The following description is a detailed description of the `Wilhelm` raspberry cultivar and the fruit produced thereby, as grown in Watsonville, Calif. between 1991 and 1994, and is believed to apply to plants of the `Wilhelm` cultivar grown in similar conditions of soil and climate elsewhere.

The `Wilhelm` fruit size on the primocane crop starts out large and declines as the harvest season progresses. The fruit size of the floricane crop is smaller with only a slight decline as the harvest progresses seasonally. The fruit of the `Wilhelm` plant is light red, releases very easily from its receptacle, and is of moderate firmness at harvest. Post harvest fruit rot resistance is intermediate in comparison with many other selections and cultivars.

The `Wilhelm` cultivar has moderate susceptibility to late leaf rust and powdery mildew. Resistance to root rots is unknown and cold tolerance of the new cultivar has not been established.

The new cultivar is particularly characterized and distinguished from other cultivars by its very attractive fruit of excellent shape with small drupelets. It is further distinguished by its bright, light red fruit color and ease of harvest. The `Wilhelm` cultivar also yields more on both primocanes and floricanes than most other known cultivars.

`Wilhelm` is distinguished from its pollen parent, selection B8-4, by having larger fruit size and greater susceptibility to late leaf rust. The new cultivar is distinguished from its seed parent, selection B175-3, by having a higher yielding capacity with more uniform fruit shape, having greater resistance to late leaf rust and having less tendency to darken after harvest.

Tables 1 and 2 below present relevant morphological information about the new raspberry `Wilhelm` cultivar.

                  TABLE 1                                                          ______________________________________                                         PLANT CHARACTERISTICS OF `Wilhelm`                                             ______________________________________                                         General                                                                        Plant size:         medium                                                     Growth habit:       erect                                                      Density of foliage: medium                                                     Productivity:       above average                                              Self fruitfulness:  self fruitful                                              Primocane fruiting:                                                            percent of cane length                                                                             about 20-25%                                               flowering as primocane:                                                        percent of total yield                                                                             about 30-50%                                               from primocane crop:                                                           Suckering tendency: low                                                        Utility of fruit:   various                                                    Canes                                                                          Primocanes                                                                     Number of fruiting laterals/cane:                                                                  about 8-14                                                 Number of canes/crown:                                                                             about 3-18                                                 Young shoot pigmentation:                                                                          weak-medium                                                Length:             about 67-72"                                               Diameter (end of 1st year):                                                    cane base:          about 0.34-0.53"                                           central 1/3 of cane:                                                                               about 0.31-0.47"                                           Depressions in cross section:                                                                      absent                                                     Prickles:                                                                      pigmentation:       unpigmented                                                density on young shoots:                                                                           very few                                                   attitude of tip:    horizontal                                                 size:               small                                                      texture:            soft                                                       presence and        irregularly                                                distribution on petioles:                                                                          distributed                                                Pubescence on canes:                                                                               present                                                    Internodal distance about 1.4-2.2"                                             (at central 1/3 of cane):                                                      Lenticels:          not visually                                                                   detectable                                                 Floricanes                                                                     Length:             about 42-70"                                               Number nodes/lateral (at mid cane):                                                                about 8-12                                                 Number of flowers/node                                                                             about 1-3                                                  (at 4th node from apex                                                         on a mid cane lateral):                                                        Leaves                                                                         Arrangement:        compound                                                   Relief between veins:                                                                              medium                                                     Leaflet number:     3-5, usually 3                                             Terminal leaflet:                                                              length:             about 4.6-5.4"                                             width:              about 2.9-3.8"                                             shape:              ovate                                                      tip:                acute to acuminate                                         base:               rounded to cordate                                         margin:             doubly serrate                                             Lateral leaflets (basal pair):                                                 overlap:            touching to                                                                    slight overlap                                             orientation:        opposite                                                   shape:              ovate                                                      tip:                acute to acuminate                                         base:               rounded                                                    margin:             doubly serrate                                             length:             about 3.5-4.9"                                             width:              about 2.0-2.8"                                             Rachis length between                                                                              about 1.2-1.4"                                             terminal leaflet and                                                           adjacent lateral leaflets:                                                     Color:                                                                         face:               Green 137B                                                 underslide:         Greyed-Green 191C                                          Petiole:                                                                       length:             about 2.5-5.3"                                             pigmentation of upper surface:                                                                     pigmented                                                  pigmentation of underside:                                                                         unpigmented                                                Stipule orientation:                                                                               erect                                                      Flowers                                                                        Flowering period:                                                              primocane:          early June to                                                                  October                                                    floricane:          late March to early                                                            June                                                       Petal:                                                                         color:              White 155D                                                 length:             about 0.22-0.28"                                           width:              about 0.09-0.13"                                           number:             5                                                          arrangement:        free                                                       Pedicel coloration: absent to very weak                                        ______________________________________                                    

                  TABLE 2                                                          ______________________________________                                         FRUIT CHARACTERISTICS OF `Wilhelm`                                             ______________________________________                                         Fruit                                                                          Harvest season:                                                                primocane:          mid-season; begins                                                             mid August; ends                                                               early to mid                                                                   November; ripens                                                               uniformly over a                                                               long period                                                                    (about 75-110 days)                                        floricane:          early to mid-season;                                                           normally begins                                                                mid to late May;                                                               ends early July;                                                               ripens uniformly                                                               over about a 45-55                                                             day period                                                 Color:                                                                         immature:           Red 39A                                                    maturing:           Red 47A                                                    mature:             Red 53A-53B                                                Dimensions:                                                                    weight:                                                                        primocane harvest:  about 2.2-5.0 g                                                                (3.1 g mean)                                               floricane harvest:  about 2.3-3.5 g                                                                (2.7 g mean)                                               length (primocane): about 0.71-0.91"                                           width (primocane):  about 0.62-0.72"                                           Soluble solids (%): about 8.1-10.6%                                                                (9.5% mean)                                                Titratable acidity  about 1.9%                                                 (% as citric acid):                                                            Seeds:                                                                         weight:             about 1.0-1.6 mg                                                               (1.3 mg mean)                                              Number drupelets/fruit:                                                                            about 83-146                                                                   (109 mean)                                                 ______________________________________                                    

In addition to the foregoing morphological description, and to provide further means for identifying the new cultivar and distinguishing it from some other somewhat similar and/or related raspberry cultivars, the new `Wilhelm` cultivar has been analyzed to obtain an indication of its genetic makeup. Specifically, leaves of the `Wilhelm`, `Hollins` (U.S. Plant Pat. No. 8,027), `Summit` (unpatented), `Isabel` (U.S. Plant patent applied for), `Sweetbriar` (U.S. Plant Pat. No. 4,486), `Joe Mello` (U.S. Plant Pat. No. 6,493) and `Godiva` (U.S. plant patent applied for) cultivars were electrophoretically analyzed, the patterns designated and procedures utilized being per those described by J. C. Cousineau and D. J. Donnelly, "Use of Isoenzyme Analysis to Characterize Raspberry Cultivars and Detect Cultivar Mislabeling," HortScience, vol. 27 (9):1023-1025 (1992). The results of the electrophoresis analysis are presented in Table 3 below, the letters representing the cultivar banding patterns for each enzyme as shown in FIG. 3, taken from the above article.

                  TABLE 3                                                          ______________________________________                                         ISOZYME BANDING                                                                PATTERNS OF `Wilhelm` COMPARED WITH                                            `Hollins`, `Summit`, `Isabel`,                                                 `Sweetbriar`, `Joe Mello` AND `Godiva`                                                   Isozyme                                                              Cultivar    PGI         MDH     PGM                                            ______________________________________                                         `Wilhelm`   D           A       C                                              `Hollins`   D           E       D                                              `Summit`    A           C       B                                              `Isabel`    A           E       C                                              `Sweetbriar`                                                                               D           D       A                                              `Joe Mello` D           E       C                                              `Godiva`    B           A       D                                              ______________________________________                                     

We claim:
 1. A new and distinct cultivar of raspberry plant named 